1. Field of the Invention
The present invention relates to image forming apparatuses and, more particularly, to an image forming apparatus which is capable of setting a waiting time for drying recording liquid.
2. Description of the Related Art
As an image forming apparatus used in a printer, a facsimile machine, a copy machine, a multi-function peripheral machine, or the like, there is an inkjet image forming apparatus. The inkjet image forming apparatus forms a visible image on a recording medium by injecting droplets of a color liquid from a liquid discharge head of a recording head onto the recording medium while conveying or moving the recording medium. The color liquid is a liquid-type coloring agent including a recording liquid, ink, etc. Hereinafter, the color liquid may be referred to as a recording liquid or ink. The recording medium is not limited to a specific material. The recording medium may be referred to as a medium to be recorded, a paper for recording, a transfer material, a recording paper, etc. The image formation performed by the inkjet image forming apparatus may include recording, printing, image printing, character printing.
When the inkjet image forming apparatus performs continuous printing, printed papers are ejected onto a paper eject tray one after another. Thus, in a case where printing is performed under a circumstance where it is difficult to dry ink in a short time or in a case where a solid image using a large amount of ink is printed on the paper, a printed paper may be ejected onto a previously ejected paper, which has been ejected onto the paper eject tray and ink discharged thereon has not been dried yet, or when a both-side printing is performed, a printed paper of which ink is discharged thereon has not been dried yet. Thus, the ink on one paper, which has not been dried completely, may be brought into contact with and rubbed by another paper or parts of a conveyance device, which causes a problem in that undried ink contaminates the printed paper.
In order to solve the above-mentioned problem, there is suggested a technique to prevent an ink contamination by setting a waiting time for drying ink. That is, a paper feeding operation is restarted after waiting for passage of the waiting time for drying ink after a preceding paper was ejected onto the paper eject tray.
According to such a conventional technique, a user sets the waiting time for ink drying so that a printing operation for a subsequent paper is started when the waiting time for drying ink has passed after a preceding paper is ejected onto a paper eject tray. However, in such a conventional technique, if a maintenance operation for a head is needed between consecutive printing operations, the waiting time for drying ink is counted after the maintenance operation has completed. Accordingly, there may be a problem in that an unnecessary waiting time must be passed even though a sufficient time for drying ink is passed due to a time spent on the maintenance operation.
Japanese Laid-Open Patent Application No. 2009-56705 discloses a technique to solve the above-mentioned problem by performing a maintenance operation to be completed within the waiting time for drying ink. However, this technique merely selects a maintenance operation, which can be completed within the waiting time for drying ink. Thus, a state where a necessary maintenance operation is not selected may be continuously maintained, which causes a problem of insufficient recovery of a head condition and incomplete maintenance.